// This file is a "Hello, world!" in Java language by OpenJDK for wandbox. import java.util.*; import java.io.*; class Main { public static void main(String[] args) { new Main().run(); } void run(){ Scanner sc=new Scanner(System.in); int N=sc.nextInt(); int[] A=new int[N]; ArrayList[] a=new ArrayList[(int)3e5+1]; for(int i=0;i(); for(int i=0;i1)dp[A[i]]=Math.max(dp[A[i]],dp[1]+1); } int ans=0; for(int v:dp)ans=Math.max(ans,v); System.out.println(ans); } void tr(Object...o){System.out.println(Arrays.deepToString(o));} } // OpenJDK reference: // http://openjdk.java.net/ // Java language references: // http://docs.oracle.com/javase